33 research outputs found
Do Two Symmetry Breaking Transitions in Photosynthetic Light Harvesting Complexes Form One, Two or More Kibble Zurek Model Topological Defects?
Kibble and Zurek proposed that rapid symmetry breaking transitions in the
hot, early universe could result in causally disconnected topological defects
such as cosmic strings. This type of first order transition has analogues in
certain second order transitions present in condensed matter such as liquid
crystals, super fluids, and charge density waves in terms of flux tubes or
vortices. Recently, we discovered that Rhodopseudomonas acidophilus
photosynthetic light harvesting complex might have different types of coherent
ground and excited states, suggesting that there are two different symmetry
breaking transitions. The B 850 ground states comprise eight identical rings
each containing 18 bacteriochlorophyll components, and each ring has undergone
a Bose Einstein phase transition to a charge density wave that lowers the
energy. The excited state coherence results from polariton formation from the
non-crossing of bosons, here an extension of exciton theory. The result is
short-lived quasi-particles with very low mass that can form an unusual BEC. We
suggest the oriented, circular B 850 and enclosed singlet B 875 compounds
create a new cavity structure with some attributes of a nano pillar. Since both
the ground and excited states should contain solitons, we envisage three fast
light pulse experiments could be able to map both the Kibble Zurek Model phase
transitions and energy transfers as a function of light intensity and time in
this complex at room temperature
Increase in ECHOvirus 6 infections associated with neurological symptoms in the Netherlands, June to August 2016
The Dutch virus-typing network VIRO-TypeNed reported an increase in ECHOvirus 6 (E-6) infections with neurological symptoms in the Netherlands between June and August 2016. Of the 31 cases detected from January through August 2016, 15 presented with neurological symptoms. Ten of 15 neurological cases were detected in the same province and the identified viruses were genetically related. This report is to alert medical and public health professionals of the circulation of E-6 associated with neurological symptoms
Norovirus outbreak in a natural playground: A One Health approach
Norovirus constitutes the most frequently identified infectious cause of disease outbreaks associated with untreated recreational water. When investigating outbreaks related to surface water, a One Health approach is insightful. Historically, there has been a focus on potential contamination of recreational water by bird droppings and a recent publication demonstrating human noroviruses in bird faeces suggested this should be investigated in future water-related norovirus outbreaks. Here, we describe a One Health approach investigating a norovirus outbreak in a natural playground. On social media, a large amount of waterfowl were reported to defecate near these playground premises leading to speculations about their potential involvement. Surface water, as well as human and bird faecal specimens, was tested for human noroviruses. Norovirus was found to be the most likely cause of the outbreak but there was no evidence for transmission via waterfowl. Cases had become known on social media prior to notification to the public health service underscoring the potential of online media as an early warning system. In view of known risk factors, advice was given for future outbreak investigations and natural playgroun
Follow-up of contacts of middle east respiratory syndrome coronavirus–infected returning travelers, the Netherlands, 2014
Notification of 2 imported cases of infection with Middle East respiratory syndrome coronavirus in the Netherlands triggered comprehensive monitoring of contacts. Observed low rates of virus transmission and the psychological effect of contact monitoring indicate that thoughtful assessment of close contacts is prudent and must be guided by clinical and epidemiologic risk factors
Increasing incidence of reported scabies infestations in the Netherlands, 2011–2021.
Introduction
Several Public Health Services and general practitioners in the Netherlands observed an increase in scabies in the Netherlands. Since individual cases of scabies are not notifiable in the Netherlands, the epidemiological situation is mostly unknown. To investigate the scabies incidence in the Netherlands, we described the epidemiology of scabies between 2011 and 2021.
Methods
Two national data sources were analysed descriptively. One data source obtained incidence data of scabies (per 1,000 persons) of persons consulting in primary care from 2011-2020. The other data source captured the number of prescribed scabicides in the Netherlands from 2011-2021. To describe the correlation between the incidence of diagnoses and the number of dispensations between 2011 and 2020, we calculated a correlation coefficient.
Results
The incidence of reported scabies has increased by more than threefold the last decade (2011-2020), mainly affecting adolescents and (young) adults. This was also clearly reflected in the fivefold increase in dispensations of scabicide medication during 2011-2021. The incidence and dispensations were at an all-time high in 2021. We found a strong correlation between the reported incidence and the number of dispensations between 2011 and 2020.
Conclusions
More awareness on early diagnosis, proper treatment and treatment of close contacts is needed
Use of PCR for detection of faecal HAV as a screening tool in an outbreak of hepatitis A in daycare centres
Infection risks of city canal swimming events in the Netherlands in 2016.
Swimming events in city canals are gaining popularity in the Netherlands, even though canal water is usually not officially designated for recreational use. Knowledge regarding the risk of infection after swimming in canals is limited. An outbreak was reported in 2015 following a canal swimming event in Utrecht, the Netherlands. Local governments were concerned about the health risks of such events. In order to assess the safety of canal swimming, the Public Health Service (PHS) prospectively investigated two city canal swimming events in 2015. In 2016, we repeated this study, aiming to prospectively determine the risks of infection during two urban swimming events, the Utrecht SingelSwim 2016 (USS) and the Amsterdam City Swim 2016 (ACS)